Improvement in sewing-machines



G. FRAME. Sewing-Machines.

. NO'I543'85.. Patented Aug.25,r1`874.

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GIBBONS FRAME, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO OSCAR PATENTOEEIcE.

F. DAVIS, OF'SAME PLACE.

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 154,385, dated August25, 1874; application filed April 8, 1874.

To all whom it may concern Be it known that I, GIBBoNs FRAME, of thecity and county of Philadelphia and State of Pennsylvania, have inventeda new and useful Improvement in Sewing-Machines; and I do herebydeclarethe following to be a clear and exact description of the naturethereof, sufficient to enable others skilled in the art to which myinvention appertains to fully understand, make, and use the same,reference being had to the accompanying drawings making part of thisspecification, in which- Figures l and 3 are side views of the deviceembodying my invention. Figs. 2 and 5 are end views thereof," and Fig. 4is a central longitudinal section thereof.

Similar letters of reference indicate corresponding parts in the severalfigures.

lt is well known that the cam or eccentric that imparts motion to thefeed-bar of a sewing-machine of a certain class is formed solid with thedriving-shaft, and that when said cam is Worn the entire shaft is nolonger serviceable. In order to withdraw said shaft the machine mustirst be removed from the table.

The loss of the shaft and difficulty of its ren moval are serious.matters, which my invention is to remedy, the same consisting of a camhaving a stem which enters a longitudinal opening in the shaft, theconstruction, operation, and advantages of which will be here inafterstated.

Referring to the drawings,A represents the shaft of the sewing 1nachine,and B the cam or eccentric whichiimparts motion to the feedl bar in themanner well known. The cam B is detached from the shaft, and has formedwith it a stem, C, which is adapted to enter an openin g formedlongitudinally in the shaft A. D represents a set-screw,whicl1 passesthrough the" shaft A, and bears against the stem ofthe cam for holdingthe latter in position. The looper or looper-hook is fitted into alongitudinal opening in the cam B, and a set-screw will be provided forholding the looper in place.

It is evident that as the cam, during usage, is in contact with theadjacent portions of the feed-bar, the former is continually subjectedto wear; therefore the feed-bar is not properly operated, and theuniformity of stitch is impaired. broken off, and in either case theshaft has to be removed.

By the use of my invention, the shaft need not be disturbed, for the oldcam will be replaced by a new cam, and the shaft continues to renderservice as previously.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

Y The feed-operating cam B, formed with stem C, and with the opening forthe shank of the hook, when combined with the shaft A, having alongitudinal opening for the stem, all constructed, arranged, andoperating substantially as and for the purpose set forth.

GIBBONS FRAME.

'Witnessesz 0. F. DAVIS,

JOHN A. WIEDEEsHEIM.

In some cases the cam is fractured or

